A Data-Over-Cable Service Interface Specification (DOCSIS) system can be used to deliver high-definition digital entertainment and telecommunications such as video, voice, and high-speed Internet to subscribers over an existing cable television network. The cable television network can take the form of an all-coax, all-fiber, or hybrid fiber/coax (HFC) network. A cable service provider, such as a multiple service operator (MSO), can deliver these services to subscribers by using a cable modem termination system (CMTS) located at a headend and cable modems (CMs) and customer premise equipment (CPE) devices, such as set-top boxes, multimedia terminal adapters (MTAs), and gateway devices, located at subscriber premises. Traffic transferred from the CMTS to the CM can be said to travel in a downstream direction on one or more downstream channels; conversely, traffic transferred from the CM to the CMTS can be said to travel in an upstream direction on one or more upstream channels.
A DOCSIS MAC domain is a logical sub-component of a CMTS that is responsible for forwarding data to and from CMs reached by a set of downstream and upstream channels associated with the MAC domain.
Channel bonding for a MAC domain can be used to increase the rate of upstream and downstream traffic forwarding between a CMTS and a CM in the MAC domain. Channel bonding was introduced in the DOCSIS 3.0 specification. Since the bonding mechanisms for downstream and upstream channel bonding are different, downstream and upstream channel bonding for a MAC domain can be configured independently. Thus, for example, a DOCSIS system can enable downstream channel bonding for a MAC domain without enabling upstream channel bonding for the same MAC domain. Then, at a later time, the DOCSIS system can enable upstream channel bonding for the MAC domain. In another example, the DOCSIS system can enable upstream channel bonding for a MAC domain, without enabling downstream channel bonding. The DOCSIS system can later enable downstream channel bonding.
To perform upstream channel bonding for a particular CMTS MAC domain of a DOCSIS system, both the MAC domain and the CMs in the MAC domain must be enabled for upstream channel bonding. In particular, pursuant to DOCSIS 3.0, to perform upstream channel bonding for a particular CMTS MAC domain of a DOCSIS system, the CMTS MAC domain and CM in the MAC domain must be enabled to operate in a multiple transmit channel (MTC) mode MTC mode. However, in existing DOCSIS systems, once the MAC domain is enabled to operate in MTC mode, the CMTS always enables MTC mode operations for any CM in the MAC domain capable of MTC mode operations that registers with the CMTS MAC domain.